SplitContainer splitContainer1 = new SplitContainer(); splitContainer1.SuspendLayout(); // add controls to splitContainer1 splitContainer1.Panel1.Controls.Add(new Button()); splitContainer1.Panel2.Controls.Add(new TextBox()); splitContainer1.ResumeLayout();In this example, we create a new SplitContainer control and add a Button control to the first panel and a TextBox control to the second panel. Before adding controls, we suspend layout using the SuspendLayout method for performance. After adding controls, we resume layout using the ResumeLayout method. Package library: System.Windows.Forms.